Sit-up cushion



FIG. 1 is a left side elevational view of a sit-up cushion showing mynew design, the right side elevational view being a mirror image of theleft side elevational view;

FIG. 2 is top plan view of the sit-up cushion;

FIG. 3 is a rear elevational view thereof;

FIG. 4 is a front elevational view thereof;

FIG. 5 is a bottom plan view thereof; and;

FIG. 6 is a perspective view thereof.

The ornamental design for a sit-up cushion, as shown.